Bone fixation system

ABSTRACT

A bone fixation system includes a bone screw having a longitudinal axis. A passage in the bone screw extends along the longitudinal axis and has a proximal opening at the proximal end of the bone screw and a distal opening at a distal end of the bone screw. A drill extends through the passage, a first end of the drill extending out the distal opening. The combination of the bone screw and the drill is self-drilling.

This is a continuation-in-part of application Ser. No. 11/071,604, filedMar. 3, 2005, which is a continuation-in-part of application Ser. No.10/864,673, filed Jun. 9, 2004, both of which are incorporated herein byreference herein.

FIELD OF THE INVENTION

The present invention relates to instrumentation and methods used in theinstallation of bone screws, alone or in combination with otherimplantable orthopedic devices. In particular, the present inventionrelates to a bone fixation system and related surgical methods.

BACKGROUND OF THE INVENTION

The bones of the human skeletal system may be compromised in variousways, including by disease or defect, such as a tumor, or an injury,such as a bone fracture. The resulting defects or abnormalities in theskeletal system often require treatment to ensure proper functioning ofthe skeletal system and the avoidance of undue pain and discomfort.

Various treatments exist for the treatment of bone fractures and/or boneor skeletal abnormalities. These treatments include, among others, theuse of internal bone fixation devices, such as bone screws, used aloneor in combination with other implantable orthopedic devices. Used alone,one or more bone screws may be employed to treat a bone fracture bystabilizing various bone pieces together and providing support duringthe healing process. Bone screws may also be used to fuse bones that areotherwise normally separate by screwing directly through one bone into asecond bone. Used in combination with other implantable devices, bonescrews may be used to secure a fixation device directly or indirectlyonto bone fracture pieces or separate bones intended to be fused.

Conventionally, bone screws are installed by performing one or more of anumber of steps. First, a pilot hole to receive the bone screw may needto be drilled and tapped to accommodate the appropriate screw threadtype. A guide wire is often installed along the desired insertion pathof the bone screw. The bone screw is screwed over the guide wire intoplace using a driver, and the guide wire is subsequently removed. Theinsertion of the bone screw may or may not additionally involve thesecuring of some type of fixation device to the bone material, eitherdirectly to the surface of the bone or though attachment to one or moreexposed portions of bone screws.

One challenge associated with the use of bone screws in bone fixationprocedures is the number of steps involved in the process. As discussedabove, certain procedures may involve, for each bone screw, drilling ahole, tapping the hole, inserting a guide wire into the hole, driving abone screw over the guide wire, and removing the guide wire. Ideally,the number of steps involved in the process should be minimized toreduce the overall time of the surgical procedure.

Ideally, a bone fixation system should also be configured for use with aminimally invasive surgical approach, such as one that utilizes smalleraccess apertures or ports rather than a large incision along the entireportion of the bone or bones being treated.

An additional challenge is minimizing the number of sharp or pointedobjects that remain within a fixated region of a patient after surgery.Such sharp or pointed objects may contribute to producing undesirableconditions related to bone structure or bone function. Ideally, thenumber of sharp or pointed objects remaining within fixated bone regionsof patients after surgery should be minimized.

There is also a need to be able to deliver fluids directly to the siteof a bone fixation procedure. Certain bone fixations heal more slowlythan others, and the healing process may be facilitated by the deliveryof certain fluids to the fixated region. It is therefore desirable tohave a vehicle for easy delivery of fluids to fixated regions of bone.

It would be desirable to provide a system and/or method that providesone or more of these or other advantageous features or addresses one ormore of the above-identified needs. Other features and advantages willbe made apparent from the present specification. The teachings disclosedextend to those embodiments that fall within the scope of the appendedclaims, regardless of whether they accomplish one or more of theabove-identified needs.

SUMMARY OF THE INVENTION

The invention relates to a bone fixation system having a bone screw witha longitudinal axis and a passage in the bone screw extending along thelongitudinal axis, the passage having a proximal opening at a proximalend of the screw and a distal opening at a distal end of the screw. Adrill extends through the passage, a first end of the drill extendingout the distal opening, whereby the combination of the bone screw andthe drill is self-drilling.

The invention further relates to a bone fixation instrumentation kithaving a bone screw with a passage extending along a longitudinal axis,the passage having a proximal opening at a proximal end of the screw anda distal opening at a distal end of the screw. The kit further containsa driver adapted to extend through the passage, whereby the combinationof the bone screw and the driver is self-drilling.

The invention further relates to a method for connecting a bone screw toa bone. The method includes the steps of opening an aperture in apatient to permit access to a bone, providing a bone screw having apassage extending along a longitudinal axis of the screw, the passagehaving a keyed portion, a proximal opening at a proximal end of thescrew, and a distal opening at a distal end of the screw. The methodfurther includes the steps of providing a drill having a shaft, acutting tip, and a keyed segment configured to interlock with the keyedportion, inserting the drill into the passage such that the cutting tipprotrudes from the distal opening and the keyed segment interlocks withthe keyed portion, and rotating the drill and screw to simultaneouslydrill a pilot hole and screw the bone screw into the bone. The methodfurther includes the step of removing the drill from the bone screwwithout also removing the bone screw from the bone.

The invention further relates to a method for attaching a bone screw toa plurality of bone segments. The method includes opening an aperture ina patient to permit access to a first bone segment and a second bonesegment, providing a bone screw having a passage extending along alongitudinal axis of the bone screw, the passage having a proximalopening at a proximal end of the bone screw and a distal opening at adistal end of the bone screw, providing a driver, inserting the driverinto the passage, driving the screw into and through the first bonesegment and onto the second bone segment, and removing the driver fromthe passage without removing the bone screw from the first and secondbone segments.

The invention is capable of other embodiments and of being practiced orbeing carried out in various ways. Alternative exemplary embodimentsrelate to other features and combinations of features as may begenerally recited in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will become more fully understood from the followingdetailed description, taken in conjunction with the accompanyingdrawings, wherein like reference numerals refer to like elements, inwhich:

FIG. 1 is a perspective view of a bone fixation system;

FIG. 2 is a perspective view of the bone fixation system of FIG. 1assembled for use;

FIG. 3 is a sectional view of the bone fixation system of FIG. 2;

FIG. 4 is a perspective view of the bone fixation system of FIG. 2positioned for use on a spine;

FIG. 5 is a perspective view of the bone fixation system of FIG. 2 afterconnection of the bone screw to the spine;

FIG. 6 is a perspective view of a bone fixation system assemblyconnected to a spine;

FIG. 7 is a perspective view of a bone fixation system;

FIG. 8 is an exploded perspective view of the bone fixation system ofFIG. 7;

FIG. 9 is a sectional view of the bone fixation system of FIG. 7 viewedalong line 1-1;

FIG. 10 is a perspective view of the bone fixation system of FIG. 7connected to a spine;

FIG. 11 is a perspective view of a bone fixation system positioned foruse on the first and second cervical vertebrae;

FIG. 12 is a perspective view of the bone fixation system of FIG. 11after insertion of the bone screw;

FIG. 13 is a perspective view of a bone fixation system positioned foruse in a trans-articular suffusion;

FIG. 14 is a perspective view of the bone fixation system of FIG. 13after insertion of the bone screw;

FIG. 15 is a perspective view of a bone fixation system positioned foruse in a trans-articular suffusion;

FIG. 16 is a perspective view of the bone fixation system of FIG. 15after insertion of the bone screw;

FIG. 17 is a perspective view of the bone fixation system of FIG. 15after insertion of a second bone screw;

FIG. 18 is a perspective view of a bone fixation system positioned foruse on a fractured odontoid process;

FIG. 19 is a perspective view of the bone fixation system of FIG. 18after insertion of the bone screw;

FIG. 20 is a perspective view of the bone fixation system of FIG. 18after insertion of a second bone screw;

FIG. 21 is a perspective view of a bone fixation system positioned foruse on a fractured clavicle bone;

FIG. 22 is a perspective view of the bone fixation system of FIG. 21after insertion of the bone screw;

FIG. 23 is a perspective view of a bone fixation system positioned foruse on a fifth metatarsal bone; and

FIG. 24 is a sectional view of the bone fixation system of FIG. 23 afterinsertion of the bone screw.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to FIG. 1, in an exemplary embodiment of the invention, a bonefixation system includes a bone anchoring element or bone screw 10. Bonescrew 10 may be used in conjunction with a driver, shown as drill 28,and holding device 24. Bone screw 10 includes a threaded portion 14 anda non-threaded upper portion, shown as post 18. A tip 12 is located atone end of bone screw 10 and a shoulder or flange 16 extends from thescrew 10 between the post 18 and threaded portion 14. At the top of thepost 18, an engagement mechanism for a screwdriver or drill, shown asrecess 20, may be utilized.

Drill 28 includes a shaft 30 sized to fit within a passage 22 (see FIG.3), a portion having cutting edges 32, and a drill tip 34. The bonescrews 10 shown in various embodiments of the invention are cannulatedto include passage 22 to accommodate drills such as drill 28.Accordingly, the drill 28 may function as a drill and as a driver forturning the screw. One advantage of the presently described embodimentof the invention is that the combination of drill 28 and bone screw 10is self-drilling, yet upon removal of the drill 28, no snap or pointedobjects remain within the patent. The term “driver” is intended togenerically refer to a drill or turning tool or a tool having bothfunctions. A keyed segment 36 of the drill is shaped to lock into recess20 so that when the drill 28 is rotated, the bone screw 10 is alsorotated. An expanded segment 38 is sized to rest upon the top of post18, and has an outer diameter that is the same as that of post 18 in apreferred embodiment. An upper keyed segment 40 provides an interfacefor a drill or other turning tool used to turn the drill 28 and the bonescrew 10.

Further referring to FIG. 1, a holding device 24 is shown as having acylindrical shape. An attachment mechanism, shown as a number of prongs26, extends from the bottom of the holding device 24 and is intended tosnap over the ridge 16 to connect the holding device 24 to the bonescrew 10. Referring to FIG. 3, the top of the holding device 24 may beshaped to engage expanded segment 38 to lock the drill 28 into place inthe bone screw 10.

Referring to FIG. 2, once assembled together, the bone screw 10, drill28, and holding device 24 create an efficient self-drilling tool fordrilling the bone screw into a selected portion of bone. The drill tip34 extends from the distal opening of the passage in the bone screw atthe bone screw tip 12 to aid in the insertion of the bone screw 10. Thesmaller diameter cutting edges 32 and sharp cutting tip 34 may bedesired by a surgeon when inserting the bone screw 10 to provide a moreaccurate placement and initial drilling point for the bone screw 10,eliminating the necessity of first drilling a pilot hole and utilizing aguide wire to guide the bone screw. Inserting a separate guide wire witha separate drill bit requires additional steps in the surgery andadditional components, complicating and perhaps lengthening the overallsurgery. The holding device 24 aids in the manipulation of the bonescrew 10 and drill 28 by preventing the drill 28 from disengaging fromthe bone screw 10 during the insertion process.

Referring to FIG. 3, the drill 28 and holding device 24 may be assembledtogether with the bone screw 10 prior to connecting the bone screw 10 tothe bone and may be assembled by sliding the components together andsnapping the holding device 24 onto the bone screw 10 without having toscrew various components together.

Further referring to FIG. 3, bone screw 10 is shown as a cannulatedscrew, having passage 22 extending the length of bone screw 10. In analternative embodiment (not shown), bone screw 10 may also befenestrated, having a series of holes extending radially outward fromrecess 22 along the length of bone screw 10. The fenestrated designallows delivery of fluids, such as bone morphogenic proteins or highdose antibiotics, to be delivered through bone screw 10 afterinstallation directly to the fixation site to assist in the fixationprocess.

Referring to FIG. 4, the assembled device depicted in FIG. 2 may beutilized to drill the bone screw 10 into a chosen bone or bones, shownas the spine, utilizing the drill 28 in combination with the bone screw10. The drill tip 34 aids in selecting a precise location for drillingthe hole for the bone screw 10.

Referring to FIG. 5, once the bone screw 10 has been screwed into thebone, the holding device 24 may be removed from the bone screw 10 bydisengaging the prongs 26, which in a preferred embodiment may bedisengaged by pulling the holding device 24 away from the bone screw 10.Referring to FIG. 6, once the holding device 24 has been removed fromthe bone screw 10, the drill 28 remains. In a preferred embodiment, thedrill may be removed from the bone screw 10 by pulling the keyed segment36 out of the recess 20. However, the user may elect to leave the drill28 in place (or replace the drill 28 with another driver configured tobe inserted into the passage 22) during assembly of a coupling mechanismas described below.

Referring to FIGS. 7-10, the bone screw 10 may be coupled to a fixationelement or linking device, shown as fixation plate 42, via a couplingmechanism 44. In use, the bone screw 10 may be inserted into a bone andlinked to other bone screws by the fixation plate 42. The length of thefixation plate 42 is chosen to accommodate the total distance betweenthe bone screws that are linked together.

Referring to FIG. 8, a receiver 46 includes a pair of wall portions 48that together form a U-shaped receiver sized to receive fixation plate42. The internal side of wall portions 48 may be threaded to engage withother instrumentation. The wall portions 48 extend upwardly from base50.

Further referring to FIG. 8, collar 52 has a threaded interior portionand a shoulder 54 that is sized to rest upon base 50. A collet 56includes a number of compressible arms 58 intended to engage with bonescrew 10 upon assembly. A lower set screw 60 has a head 62 that may beconfigured to be grasped by a tool, such as the hex-head configurationshown in FIG. 8. A threaded portion 64 is configured to engage with theinternal threads of the collar 52 during assembly. A pair of retainingrings 66, 68 engage either side of fixation plate 42, the lowerretaining ring 66 resting upon collar 52 and the upper retaining ring 68compressed between the fixation plate 42 and an upper set screw 70. Theupper set screw 70 has a threaded portion 72 intended to engage with thethreaded interior side of wall portions 48 of the receiver 46 uponassembly. The upper set screw 70 may have a head configuration designedto be engaged by a wrench or other tightening tool.

Referring to FIG. 9, while an upper portion of the interior of collar 52is threaded to engage with lower set screw 60, the lower portion is notthreaded but has a tapered interior portion having a more narrowdiameter at the bottom of the collar 52. During assembly of the fixationsystem, the collar 52 is dropped into the receiver 46, the shoulder 54resting upon the base 50. Note that each of the components forming thecoupling mechanism has an interior channel or aperture configured toallow the components to be placed upon and encircle the post 18. Thecollet 56 is placed into collar 52, the outer diameter of the collet 56being greater along a portion of the longitudinal axis of collet 56 thanthe interior diameter of collar 52, as shown in FIG. 8. The lower setscrew 60 may then be threaded into collar 52, thus engaging collet 56and pushing collet 56 downward through the collar 52 until thecompressible arms 58 are forced to grip and be secured to post 18.Engagement of the post 18 by the collet 56 locks the collet 56 and theother components of the coupling mechanism into place relative to thebone screw 10 for fixation to the fixation plate 42.

Note that the collet 56 may be locked onto post 18 at any position alongthe longitudinal axis of post 18, affording flexibility in the placementof the coupling mechanism components. In other bone screw embodiments,the collet may engage with the threaded portion of the bone screw. Theflexibility in placement of the collet is important due to thevariability in placement of the bone screw 10 depending on the anatomyof the patient. Once the receiver 46, collar 52, and collet 56 arelocked into place onto bone screw 10, the fixation plate 42 may belinked to the bone screw 10 by placing retainer rings 66, 68 over thepost 18 on either side of the fixation plate 42 and locking the fixationplate 42 into place by threading upper set screw 70 into receiver 46 tocomplete the assembly.

Further referring to FIG. 9, the recess 20 extends into the bone screw10 to create a keyed portion of passage 22 that extends the length ofthe bone screw 10. The keyed portion may serve as an engagement pointfor a driver as discussed above.

Referring to FIG. 10, the embodiment of the bone fixation system shownin FIGS. 7-9 is shown installed into a patient's spine. In practice, thebone screws 10 may be individually installed prior to the installationof the fixation plate 42 across the multiple bone screws 10.

Further referring to FIGS. 7-10, the fixation device or plate 42 asshown is configured to be attached from the top of and afterinstallation of bone screws 10. In an alternative embodiment (notshown), a fixation plate with multiple though-holes may be configured tobe applied directly to one or more bones or bone fragments to be fusedtogether prior to the installation of bone screw 10. The through holesare configured to allow bone screw 10 to secure the fixation plate 42 tothe bone. Alternatively, a single aperture in the fixation plate may beprovided and configured to accept multiple bone screws 10. Afterlocating the fixation plate across the fracture site or joint, bonescrews 10 may be driven though the through-holes and into the bone onboth sides of the fracture site or joint, thereby securing the fixationplate 42 to the pieces of bone to be joined.

The various bone fixation or instrumentation systems described herein asexemplary embodiments of the invention may be utilized in theperformance of bone fixation procedures using a streamlined method thatis intended to simplify and shorten conventional bone fixationprocedures. Prior to operating, imaging of the patient may be utilizedto determine the number and locations of bone screws that will berequired as part of the procedure. Further, an image guidance system maybe utilized as part of the procedure to aid in the placement of thevarious components. In the case of an open procedure, an entry site iscreated in the patient along the portion of the bone into which the bonescrews will be inserted. In the case of a minimally invasive procedure,individual entry ports may be utilized for implantation of individualbone screws. Certain embodiments of the invention described herein areparticularly suited to a minimally invasive approach because thecoupling components are placed upon the screw from the top, allowinginsertion and connection of the components via the small percutaneousaperture created for the screw itself in contrast to other designsrequiring the use of coupling components that are not in line with thelongitudinal axis of the screw, which may require an open procedure.

After creating the entry site and determining the point of insertion ofa bone screw, the drill may be inserted into the bone screw, using theholding device to hold the drill in place, if desired, and utilized todrill into the bone simultaneously with the bone screw.

In addition to the embodiment of the invention shown in use on a portionof the spine in FIGS. 4-6, the invention is also applicable to othersurgical procedures involving a bone anchoring element or bone screw.FIGS. 11-24, discussed below, show various other embodiments of theinvention as applied to various portions of the skeletal system.

Referring to FIGS. 11-12, in an exemplary embodiment of the invention,the bone screw 10 and associated drill 28 are used in a posteriortrans-articular fixation procedure of the first (C1) and second (C2)cervical vertebrae 74, 76. An entry site is created posterior the C2vertebra 76 and an insertion point on the surface of the C2 vertebra 76is determined. The drill 28 is then inserted into the bone screw 10 andthe screw is driven from the insertion point through the C2 vertebra 76and into the C1 vertebra 74, thereby fixating the two bones. The drill28 is then removed from the bone screw 10 located in the fixated region.A second bone screw 10 (not shown) is then inserted in a similar fashionto ensure proper fixation of the bones. The two bone screws 10 arenormally offset to opposite sides of the midline of the vertebrae 74,76.

Referring to FIGS. 13 and 14, in another exemplary embodiment of theinvention, the bone screw 10 and associated drill 28 are used in atrans-articular suffusion procedure of the lower lumbar region involvingthe fourth (L4) and fifth (L5) lumbar vertebrae 78, 80. An entry site iscreated posterior the L4 vertebra 78 and an insertion point on thesurface of the L4 vertebra 78 is determined. The drill 28 is theninserted into the bone screw 10 and the screw is driven from theinsertion point through the L4 vertebra 78 and into the L5 vertebra 80,thereby fixating the two bones. The drill 28 is then removed from thebone screw 10 located in the fixated region.

Referring to FIGS. 15-17, in another exemplary embodiment of theinvention, the bone screw 10 and associated drill 28 are used in alumbosacral fixation procedure involving the fifth lumbar (L5) and firstsacral (S1) vertebrae 82, 84. An entry site is created posterior the L5vertebra 82 and a first insertion point on the surface of the L5vertebra 82 is determined. The drill 28 is then inserted into the bonescrew 10 and the screw is driven from the insertion point through the L5vertebra 82 and into the S1 vertebra 84, thereby fixating the two bones.The drill 28 is then removed from the bone screw 10 located in thefixated region. A second bone screw 10 is then inserted in a similarfashion to ensure proper fixation of the bones. The two screws 10 arenormally offset to opposite sides of the midline of the vertebrae 82,84.

Referring to FIGS. 18-20, in another exemplary embodiment of theinvention, the bone screw 10 and associated drill 28 are used in afixation procedure of a fracture of the odontoid process 86 of the C2vertebra 88. An entry site is created anterior the C2 vertebra 88 and afirst insertion point on the surface of the C2 vertebra 88 isdetermined. The drill 28 is then inserted into the bone screw 10 and thescrew is driven from the insertion point through the C2 vertebra 88 andinto the odontoid process 86, thereby fixating the fracture. The drill28 is then removed from the bone screw 10 located in the fixated region.A second bone screw 10 may be inserted in a similar fashion through asecond insertion point, as shown in FIG. 20, to ensure proper fixationof the fracture. The two screws 10 are normally offset to opposite sidesof the midline of the C2 vertebrae 88.

Referring to FIGS. 21 and 22, in another exemplary embodiment of theinvention, the bone screw 10 and associated drill 28 are used in aninternal fixation procedure of a fractured clavicle 94. For a claviclefracture such as the one shown, an entry site is chosen to allowinsertion of a bone screw 10, across the fracture site in thelongitudinal direction of the clavicle bone. The drill 28 is theninserted into the bone screw 10 and the screw is driven from theinsertion point on the first fractured portion 90, through the fracturesite along the longitudinal direction of the clavicle bone 94, and intoa second fractured portion 92. The drill 28 is then removed from thebone screw 10 located in the fixated region.

Referring to FIGS. 23 and 24, in another exemplary embodiment of theinvention, the bone screw 10 and associated drill 28 are used in afixation procedure of the fifth metatarsal 100. For a metatarsalfracture such as the one shown, an entry site is chosen to allowinsertion of a bone screw 10 across the fracture site in thelongitudinal direction of the metatarsal bone 100. The drill 28 is theninserted into the bone screw 28 and the screw is driven from theinsertion point into a first fractured portion 96, through the fracturesite along the longitudinal direction of the metatarsal bone 100, andinto a second fractured portion 98. The drill 28 is then removed fromthe bone screw 10 located in the fixated region.

If a fixation plate is to be installed, a portion of each of the bonescrews is left exposed outside of the bone material as shown in FIG. 9.After installation of the desired number of bone screws, the couplingmechanism is utilized to connect the bone screws to a linking device,such as a fixation rod or plate as shown and described herein. In thecase of a minimally invasive procedure, multiple drills may be utilizedto aid in the installation of the coupling components and the linkingdevice may be threaded beneath the patient's skin between the variousbone screws that are being linked to each other. Alternatively, asdiscussed above, the fixation plate 42 may be placed directly onto thebone or bones prior to installation of the bone screws 10. Afterpositioning the fixation plate 42 onto the bone, bone screws 10 aredriven through the fixation plate 42 and into the bone, thereby securingthe fixation plate 42 directly to the bone.

In the embodiments described herein, drill 28 is provided with drill tip34 to make the combination of bone screw 10 and drill 28 self-drilling.It should be noted that after insertion of bone screw 10, drill 28 maybe removed, thereby ensuring that no sharp or pointed objects (e.g.,drill tip 34) remain within the patent.

While the detailed drawings and specific examples given herein describevarious exemplary embodiments, they serve the purpose of illustrationonly. It is to be understood that the invention is not limited in itsapplication to the details of construction and arrangements ofcomponents set forth in the preceding description or illustrated in thedrawings. It should be noted that the components and/or assemblies ofthe bone fixation system may be constructed from various materials knownin the art. Further, while several examples show the invention in thecontext of various skeletal regions, the invention is applicable tosurgical procedures involving other regions not described in theembodiments contained herein. Further, the order of performance of themethod steps described with respect to bone fixation proceduresutilizing the various embodiments of the present invention may vary.Furthermore, other substitutions, modifications, changes and omissionsmay be made in the design, operating conditions, and arrangements of theexemplary embodiments without departing from the scope of the inventionas expressed in the appended claims.

1. A bone fixation system, comprising: a bone screw having alongitudinal axis; a passage in the bone screw extending along thelongitudinal axis, the passage having a proximal opening at a proximalend of the bone screw and a distal opening at a distal end of the bonescrew; and a drill extending through the passage, a first end of thedrill extending out the distal opening, whereby the combination of thebone screw and the drill is self-drilling.
 2. The bone fixation systemof claim 1, wherein a second end of the drill extends out the proximalopening.
 3. The bone fixation system of claim 1, further comprising atubular holding device adapted to be placed over the drill and removablycoupled to the bone screw.
 4. The bone fixation system of claim 3,wherein the holding device has a plurality of prongs and the bone screwhas a flange and wherein the prongs snap onto the flange to couple theholding device to the bone screw.
 5. The bone fixation system of claim1, wherein the passage comprises a keyed portion and the drill comprisesa keyed segment, the keyed segment and the keyed portion configured tointerlock with one another wherein rotation of the drill results in acorresponding rotation of the bone screw.
 6. The bone fixation system ofclaim 1, further comprising: a second drill; a second bone screw havinga second longitudinal passage configured to receive the second drill; alinking device configured to connect the bone screw to the second bonescrew; and a coupling mechanism adapted to couple the linking device tothe bone screw, wherein the coupling mechanism comprises at least oneannular component sized to be fitted over the bone screw and the drill.7. The bone fixation system of claim 6, wherein the at least onecomponent is a collet configured to be secured to the bone screw.
 8. Thebone fixation system of claim 6, wherein the linking device is afixation plate.
 9. The bone fixation system of claim 1, wherein the bonescrew further comprises a plurality of holes extending radially outwardfrom the passage along the longitudinal axis of the bone screw.
 10. Abone fixation instrumentation kit, comprising: a bone screw having apassage extending along a longitudinal axis of the bone screw, thepassage having a proximal opening at a proximal end of the screw and adistal opening at a distal end of the screw; and a driver adapted toextend through the passage, whereby the combination of the bone screwand the driver is self-drilling.
 11. The bone fixation instrumentationkit of claim 10, wherein the driver is a drill and the drill is longerthan the passage whereby an end of the drill is adapted to extend outthe proximal opening.
 12. The bone fixation instrumentation kit of claim11, further comprising a tubular holding device adapted to be placedover the drill and removably coupled to the bone screw.
 13. The bonefixation instrumentation kit of claim 11, wherein the passage comprisesa keyed portion and the drill comprises a keyed segment, the keyedsegment and the keyed portion configured to interlock with one anotherwherein rotation of the drill results in a corresponding rotation of thebone screw.
 14. The bone instrumentation kit of claim 10, furthercomprising: a second driver; a second bone screw having a secondlongitudinal passage configured to receive the second driver; a linkingdevice configured to connect the bone screw to the second bone screw;and a coupling mechanism adapted to couple the linking device to thebone screw, wherein the coupling mechanism comprises at least oneannular component sized to be fitted over the bone screw and the driver.15. The bone fixation instrumentation kit of claim 14, wherein the atleast one annular component is a collet configured to be secured to thebone screw.
 16. The bone fixation instrumentation kit of claim 10,wherein the bone screw further comprises a plurality of holes extendingradially outward from the passage along the longitudinal axis of thebone screw.
 17. The bone fixation instrumentation kit of claim 14,wherein the linking device is a fixation plate.
 18. A method forconnecting a bone screw to a bone, comprising: opening an aperture in apatient to permit access to a bone; providing a bone screw having apassage extending along a longitudinal axis of the bone screw, thepassage having a keyed portion, a proximal opening at a proximal end ofthe bone screw, and a distal opening at a distal end of the bone screw;providing a drill having a shaft, a cutting tip, and a keyed segmentconfigured to interlock with the keyed portion; inserting the drill intothe passage wherein the cutting tip protrudes from the distal openingand the keyed segment interlocks with the keyed portion; rotating thedrill and therefore the bone screw to drill a pilot hole and screw thebone screw into the bone; and removing the drill from the bone screwwithout also removing the bone screw from the bone.
 19. The method ofclaim 18, wherein the shaft protrudes from the proximal opening andextends through the aperture in the patient.
 20. The method of claim 18,further comprising: providing a tubular holding device configured to beplaced over the drill to lock the drill to the bone screw; and couplingthe holding device to the bone screw.
 21. The method of claim 20,further comprising removing the holding device from the bone screw. 22.A method for attaching a bone screw to a plurality of bone segmentscomprising: opening an aperture in a patient to permit access to a firstbone segment and a second bone segment; providing a bone screw having apassage extending along a longitudinal axis of the bone screw, thepassage having a proximal opening at a proximal end of the bone screwand a distal opening at a distal end of the bone screw; providing adriver; inserting the driver into the passage; driving the screw intoand through the first bone segment and into the second bone segment;removing the driver from the passage without removing the bone screwfrom the first and second bone segments.
 23. The method of claim 22,wherein the first bone segment is a first vertebral bone and the secondbone segment is a second vertebral bone, wherein the first vertebralbone is adjacent the second vertebral bone.
 24. The method of claim 23,wherein the first vertebral bone is a first cervical vertebra and thesecond vertebral bone is a second cervical vertebra.
 25. The method ofclaim 24, further comprising: providing a second bone screw having apassage extending along a longitudinal axis of the second bone screw;inserting the driver into the passage of the second bone screw; drivingthe second bone screw into and through the first bone segment and intothe second bone segment; removing the driver from the passage of thesecond bone screw without removing the second bone screw from the firstand second bone segments.
 26. The method of claim 23, wherein the firstbone segment is fourth lumbar vertebra and the second bone segment isfifth lumbar vertebra.
 27. The method of claim 23, wherein the firstbone segment is a fifth lumbar vertebra and the second bone segment isfirst sacral vertebra.
 28. The method of claim 27, further comprising:providing a second bone screw having a passage extending along alongitudinal axis of the second bone screw; inserting the driver intothe passage of the second bone screw; driving the second bone screw intoand through the first bone segment and into the second bone segment;removing the driver from the passage of the second bone screw withoutremoving the second bone screw from the first and second bone segments.29. The method of claim 22, wherein the first bone segment comprises afirst portion of a fractured bone and the second bone segment comprisesa second portion of the fractured bone.
 30. The method of claim 29,wherein the fractured bone is a second cervical vertebra and the secondportion is the odontoid process of the second cervical vertebra.
 31. Themethod of claim 30, further comprising: providing a second bone screwhaving a passage extending along a longitudinal axis of the second bonescrew; inserting the driver into the passage of the second bone screw;driving the second bone screw into and through the first bone segmentand into the second bone segment; removing the driver from the passageof the second bone screw without removing the second bone screw from thefirst and second bone segments.
 32. The method of claim 29, wherein thefractured bone comprises a clavicle bone.
 33. The method of claim 29,wherein the fractured bone comprises a fifth metatarsal bone.